In cats, black fur is dominant over brown fur. If two heterozygous cats have a litter of three kittens, what is the probability that all three kittens will be brown?

1/4 or 25% probability of 3 brown kittens.

Explanation:

Black fur is dominant = B

Brown fur is recessive = b

Heterozygous cats = Bb

Cross between two heterozygous cats

Bb x Bb

The result of that genotype will be BB, Bb, Bb, bb

BB = 1/4 or 25%

Bb (2) = 2/4 or 50%

bb = 1/4 or 25%

So, brown fur (bb) has 25% chance in three kittens.